vooya is a raw video sequencer player for Windows, macOS and Linux and has, beginning with version 1.6, an open plugin API. The plugin mechanism is based on standard shared libraries loaded at runtime, so plugins can be written in any language suitable for creating shared libraries, notably C/C++, Rust or Objective-C.

Below you can see vooya's processing chain and where plugin callbacks can kick in (the items marked yellow). These are:

• Input Provide custom input to vooya, from any source
• Histogram Get access to the calculated histogram data
• Native I/O Callback with the raw video data for each frame
• RGB 32bit I/O Callback with the rendered data in RGB right before display
• EOTF Add custom transfer functions to vooya's existing ones
• Diff View Pixelwise callback function for difference views (not shown below)

All is explained in voo_plugin.h and some examples are given in the examples-folder. Run the make_* scripts to build them all for your platform and be sure to let vooya's plugin directory point to our examples.

The whole functionality of your plugin is described by you in voo_describe(), where the main describing structure is to be filled:

VP_API void voo_describe( voo_plugin_t *p_plugin )
{
	/* mandatory line */
	p_plugin->voo_version = VOO_PLUGIN_API_VERSION;
	p_plugin-> ...
}

Everything is based on callbacks you provide as function pointers. For example, you could write a function named invert which inverts a 32bit RGB pixel, and hand that function over to vooya like so:

	p_plugin->callbacks[0].uid = "voo.test.rgb_invert";
	p_plugin->callbacks[0].name = "RGB Inverter";
	p_plugin->callbacks[0].description = "Inverts each channel";
	p_plugin->callbacks[0].type = vooCallback_RGBOut;
	p_plugin->callbacks[0].method_rgb_out = invert;

Turn on Plugin debugging in vooya's preferences to get some console output. Note the plugin API is still experimental.

• on Windows, open a Visual Studio Command Prompt (64bit or 32bit, according to your platform), cd to the root directory and type make_win.bat
• on Linux, open a terminal, cd to the root directory and run ./make_unix.sh
• on macOS, make sure you have clang installed (XCode command line tools) open a terminal, cd to the root directory and run ./make_osx.sh

The MOV/MP4 file reader plugin called vooPLUS.